gistfile1.txt

-> (set-member? s 3)
; s: contract violation
;   expected a procedure that accepts 1 mandatory argument without any keywords
;   given: 3
;   in: the 2nd argument of
;       method set-member? with contract (-> set? (-> number? number?)
;         boolean?)
;       (set/c (-> number? number?))
;   contract from: (definition s)
;   blaming: top-level
;   at: readline-input:2.17
; [,bt for context]